XZ could reveal what really happened to Max Shacknai while under Rebecca's care. The truth about what happened to Max and why Rebecca really committed suicide needs to be revealed.
Reinvestigating both deaths would accomplish that. Lawsuits that bankrupt victims is a despicable way to go.
If Dina is considering such a thing, it reflects very poorly on her and would make most people question her sanity. If she wants to do this, she's seriously mentally ill.